Difference between two directories in Linux [close

Question

I'm trying to find the files existing in one directory but not in the other, I tried to use this command:

diff -q dir1 dir2

The problem with the above command that it finds both the files in dir1 but not in dir2 as well as the files in dir2 but not in dir1,

I am trying to find the files in dir1 but not in dir2 only.

Here's a small sample of what my data looks like

dir1    dir2    dir3
1.txt   1.txt   1.txt
2.txt   3.txt   3.txt
5.txt   4.txt   5.txt
6.txt   7.txt   8.txt

Another question on my mind is how can I find the files in dir1 but not in dir2 or dir3 in a single command?

Answer 1

The accepted answer will also list the files that exist in both directories, but have different content. To list ONLY the files that exist in dir1 you can use:

diff -r dir1 dir2 | grep 'Only in' | grep dir1 | awk '{print $4}' > difference1.txt

Explanation:

• diff -r dir1 dir2 : compare
• grep 'Only in': get lines that contain 'Only in'
• grep dir1 : get lines that contain dir

Answer 2

A good way to do this comparison is to use find with md5sum, then a diff.

Example:

Use find to list all the files in the directory then calculate the md5 hash for each file and pipe it to a file:

find /dir1/ -type f -exec md5sum {} \; > dir1.txt

Do the same procedure to the another directory:

find /dir2/ -type f -exec md5sum {} \; > dir2.txt

Then compare the result two files with "diff":

diff dir1.txt dir2.txt

This strategy is very useful when the two directories to be compared are not in the same machine and you need to make sure that the files are equal in both directories.

Another good way to do the job is using git

git diff --no-index dir1/ dir2/

Best regards!

Answer 3

Another (maybe faster for large directories) approach:

$ find dir1 | sed 's,^[^/]*/,,' | sort > dir1.txt && find dir2 | sed 's,^[^/]*/,,' | sort > dir2.txt
$ diff dir1.txt dir2.txt

The sed command removes the first directory component thanks to Erik`s post)